Learning More About Harvesting Bush

On 12 – 16 November 2013, CCF hosted a visiting researcher Dr. Arvo Leinonen, Chief Research Scientist at Technical Research Centre of Finland (VTT) Finland. Dr Leinonen, an engineer by profession, previously visited CCF in 2007 and conducted a feasibility study on electricity and pyrolisis oil production from encroaching Acacia wood chips in Namibia (Research report NO VTT-R077612-07/14.4.2008).

Namibian farmlands provide refuge to the cheetah populations and its prey, yet bush encroachment – the increase in woody density – has become a common environmental concern. Open thorn-bush savannas are turning into dense vegetation partly due to anthropogenic influence. This change in vegetation structure has direct consequences on the functioning of ecosystems and ecological services. In addition, it could potentially threaten agriculture and tourism which are key sectors in the Namibian economy.

CCF received a grant from Tillvaxtverket, the Swedish Agency for Economic and Regional Growth to assist in acquisition of harvest machinery. We acquired a small mechanized harvest machine (VIMEK 404T) from a Swedish manufacturer and are testing the productivity of this mechanised harvester and comparing its productivity to manual harvesting (~15 men) in demarcated plots.

Manual harvesting of Acacia biomass is practiced widely in Namibia. However, the use of mechanised tools attached to the harvester such as the Nisula and Bracke are unknown. About 26 million hectares of the Namibian farmland is affected by bush encroachment. The common culprits of bush encroachment are Acacia mellifera (Black thorn), Acacia erubescens (Blue thorn), Acacia reficiens (False-umbrella thorn), Dichrostachys cineria (Sickle bush), Terminalia prunoides (Purple-pod terminalia), Terminalia sericea (Silver-leave terminalia) and Colophospermum mopane (Mopane tree). Due to the abundance of acacia biomass, we’re investigating different harvesting methods in order to increase productivity and restore adequate habitat for the local biodiversity, consequently, the reduction in human-wildlife conflict.

Dr. Leinonen is one of the world’s experts in forest logistics and will compile a formal analysis of the machinery that will help us to utilize it effectively to increase harvesting of thickened thornbush.